Viral nervous necrosis （VNN） causes high mortality in marine fish, especially in the grouper, worldwide and in China. Since there is no effective vaccine or drug to deal with VNN, early detection and prevention is i...Viral nervous necrosis （VNN） causes high mortality in marine fish, especially in the grouper, worldwide and in China. Since there is no effective vaccine or drug to deal with VNN, early detection and prevention is important to block its outbreak. In this study, a reverse transcription-polymerase chain reaction （RT-PCR） was developed for the rapid, convenient, and sensitive detection of the VNN pathogen, nervous necro- sis virus （NNV）, in the grouper. The whole process was completed within 3.5 h from the RNA extraction to PCR product visualization. The detection limit of this method was 200 copies of NNV RNA standard, which corresponded to 200 copies of virus particles. This RT-PCR method was specific to the NNV detection with no cross-reactivity to other fish viral disease pathogens, such as infectious pancreatic necrosis virus （IPNV）, infectious hematopoietic necrosis virus （IHNV）, spring viraemia of carp virus （SVCV）, epizootic haematopoietic necrosis virus （EHNV）, and large yellow croaker iridovirus （LYC1V）. With this method, the orange-spotted grouper （Epinephelus coioides） fry from hatcheries with or without incidence of the VN- N epidemic in Fujian Province were detected. The results showed that all or 93% of the fry from the two hatcheries with incidence of the epidemic were diagnosed as positive, while 40% or 25% of fry from the t- wo hatcheries without the VNN epidemic were also detected as NNV positive, indicating that this RT-PCR method can be used for rapid, sensitive detection of NNV infection and applied in the VNN epidemic alert.展开更多
Crossbreeding between Epinephelas coioides （ ♀ ） and Epinephelus lanceolatus （♂） was conducted by artificial insemination. Fertilized eggs were col- lected at 0, 30, 90 s, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,...Crossbreeding between Epinephelas coioides （ ♀ ） and Epinephelus lanceolatus （♂） was conducted by artificial insemination. Fertilized eggs were col- lected at 0, 30, 90 s, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 min post-insemination respectively, which were fixed by Smith＇s solution, embedded by paraffins and stained by H.E. According to the characteristics of Epinephelus coioides eggs, tissue section method was modified. The results showed that the sperms of Epinephelus lanceolatus rapidly entered the eggs of Epinephelus coioides at 30 s - 1 rain post-insemination. Observation results of tissue sections showed that mature eggs of Epinephelus coioides remained at metaphase of secondary maturation division. The eggs were activated after sperm penetration into the egg. With the develop- ment of secondary maturation division, at 2 rain post-insemination, eggs reached the metaphase of secondary maturation division ; at 3 - 6 rain post-insemination, sperm asters appeared; at 5 min post-insemination, eggs extruded secondary polar body; at 7 -15 rain post-insemination, male pronucleus and female pronucleus moved closer to each other and fused finally, forming a clear junction line; subsequently, zygote nucleus formed and karyotheca became faint; at 15 min pest-insem- ination, first karvokinetic division was develoued.展开更多
Aquaculture production efficiency may increase by using feed additives. This study investigated the effects of different dietary additives [w/w: 2% small peptides, 0.01% probiotics( Bacillus licheniformis) and 0.2% pr...Aquaculture production efficiency may increase by using feed additives. This study investigated the effects of different dietary additives [w/w: 2% small peptides, 0.01% probiotics( Bacillus licheniformis) and 0.2% prebiotics(inulin)] on growth performance, digestive enzyme activities, and oxidative stress in juvenile Epinephelus coioides reared in artificial seawater of two salt concentrations(13.5 vs. 28.5). Weight gain rate was significantly higher in fish fed the diet supplemented with small peptides, B. licheniformis, inulin, or synbiotics than that in fish fed the basal diet; the greatest weight gain rate was found in fish fed the small peptide treatment [56.0% higher than basal diet]. Higher feed efficiency was detected in fish fed the diet supplemented with small peptides than that of fish in the other dietary treatments. Total protease activity in the stomach and intestines was highest in fish fed the small peptide-treated diet, whereas lipase activity was highest in those fed synbiotics(combination of Bacillus licheniformis and inulin) than that in fish fed the other treatments. Antioxidant enzyme(total superoxide dismutase and catalase) activities and hepatic malondialdehyde content were higher in fish receiving the dietary supplements and maintained in artificial seawater containing 13.5 salinity compared with those in the control(28.5). Hepatic catalase activity in grouper fed the diets with small peptides or synbiotics decreased significantly compared with that in control fish. Overall, the three types of additives improved growth rate of juvenile grouper and digestive enzymes activities to varying degrees but did not effectively improve antioxidant capacity under low-salinity stress conditions.展开更多
Using multi-molecular marker technologies and based on morphological criteria, the genetic relationship between Epinepheelus malabaricus and E, coioides was examined in the hope of resolving the long-standing issue of...Using multi-molecular marker technologies and based on morphological criteria, the genetic relationship between Epinepheelus malabaricus and E, coioides was examined in the hope of resolving the long-standing issue of identifying these two species. Results showed that： （ 1 ） E. coioides and E. malabaricus should be identified as two species, the consistency of mitochondrial DNA cytochrome b gene sequence between E. malabaricus and E. coioides is 94.4%, and the genetic similarity by AFLP was 0.753 9 ; （2） Hybridization exists between E. malabaricus and E. coioides, the specific RAPD and AFLP fragments are found to be useful in the identification of these two species, and the genetic properties （both with exterior and inheritance） of hybrid is significantly biased to the male parents ; and （3） AFLP was a potentially powerful tool in constructing the genetic linkage map for these two groupers.展开更多
Effects of water temperature （17, 21, 25, 30 and 35℃） and body size （14.75-281.41 g initial body weight） on food consumption, growth, feed conversion, and dry matter content in orange-spotted grouper fed to satia...Effects of water temperature （17, 21, 25, 30 and 35℃） and body size （14.75-281.41 g initial body weight） on food consumption, growth, feed conversion, and dry matter content in orange-spotted grouper fed to satiation were investigated. The combined effect of temperature （T, ℃） and body weight （W, g） on maximum food consumption （Cmax, g/day） was described as： InCmax=-7.411＋0.828 InW＋0.317T4）.004 7T2, and the optimum feeding temperature was 33.9℃. The combined effect of temperature and body weight on growth （G） was described as： lnG=-4.461-0.2081nW＋0.394T-0.006 3T^2. The optimum growth temperature was 31.4℃, whereas overall growth rates were high at 25, 30 and 35 ℃. Feed conversion efficiencies （FCE, %）, increasing first and then decreasing with increasing temperature, averaged from 1.8 to 2.1 in terms of dry weight of food fish. The optimum temperature for FCE tended to be lower than that for growth or feeding. Dry matter content increased with both increasing water temperature （17, 25, 30 and 35℃） and body weight, and the combined effect of temperature and body weight on dry matter content （DM, %） was described as： lnDM =3.232＋0.01 4 lnW-0.004 4T＋0.001 2TInW.展开更多
Serum biochemical parameters are important aspects in the management of endangered species. The values of these parameters can be used for confirming the maturity and for monitoring any changes in the quality of water...Serum biochemical parameters are important aspects in the management of endangered species. The values of these parameters can be used for confirming the maturity and for monitoring any changes in the quality of waters and related soils. The aim of this research was to determine the reference values of biochemical factors in Acantopagrus latus and Epinephelus coioides. Blood samples were collected from captured fish from coastal waters of Chabahar (Ramin waterfront). Serum levels of glucose, Blood Urea Nitrogen (BUN), cholesterol (CHO), triglyceride, total protein, albumin, calcium (Ca2+), phosphorus (P), sodium (Na+), bilirubin and potassium (K+) were measured. The results showed that the levels of albumin and bilirubin in E. coioides were significantly higher than A. latus and there were significant differences in all of the serum values (except P and glucose) between A. latus and E. coioides (P < 0.05). It can be concluded that the values of blood biochemical parameters may be affected by physiological factors such as the species of fish.展开更多
基金The National Basic Research Program under contract No.2012CB114402the National High Technology Research and Development Program of China (863 Program) under contract No.2012AA092202Scientific Research Project of Marine Public Welfare Industry of China under contract No.200905020-07
文摘Viral nervous necrosis （VNN） causes high mortality in marine fish, especially in the grouper, worldwide and in China. Since there is no effective vaccine or drug to deal with VNN, early detection and prevention is important to block its outbreak. In this study, a reverse transcription-polymerase chain reaction （RT-PCR） was developed for the rapid, convenient, and sensitive detection of the VNN pathogen, nervous necro- sis virus （NNV）, in the grouper. The whole process was completed within 3.5 h from the RNA extraction to PCR product visualization. The detection limit of this method was 200 copies of NNV RNA standard, which corresponded to 200 copies of virus particles. This RT-PCR method was specific to the NNV detection with no cross-reactivity to other fish viral disease pathogens, such as infectious pancreatic necrosis virus （IPNV）, infectious hematopoietic necrosis virus （IHNV）, spring viraemia of carp virus （SVCV）, epizootic haematopoietic necrosis virus （EHNV）, and large yellow croaker iridovirus （LYC1V）. With this method, the orange-spotted grouper （Epinephelus coioides） fry from hatcheries with or without incidence of the VN- N epidemic in Fujian Province were detected. The results showed that all or 93% of the fry from the two hatcheries with incidence of the epidemic were diagnosed as positive, while 40% or 25% of fry from the t- wo hatcheries without the VNN epidemic were also detected as NNV positive, indicating that this RT-PCR method can be used for rapid, sensitive detection of NNV infection and applied in the VNN epidemic alert.
文摘Crossbreeding between Epinephelas coioides （ ♀ ） and Epinephelus lanceolatus （♂） was conducted by artificial insemination. Fertilized eggs were col- lected at 0, 30, 90 s, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 min post-insemination respectively, which were fixed by Smith＇s solution, embedded by paraffins and stained by H.E. According to the characteristics of Epinephelus coioides eggs, tissue section method was modified. The results showed that the sperms of Epinephelus lanceolatus rapidly entered the eggs of Epinephelus coioides at 30 s - 1 rain post-insemination. Observation results of tissue sections showed that mature eggs of Epinephelus coioides remained at metaphase of secondary maturation division. The eggs were activated after sperm penetration into the egg. With the develop- ment of secondary maturation division, at 2 rain post-insemination, eggs reached the metaphase of secondary maturation division ; at 3 - 6 rain post-insemination, sperm asters appeared; at 5 min post-insemination, eggs extruded secondary polar body; at 7 -15 rain post-insemination, male pronucleus and female pronucleus moved closer to each other and fused finally, forming a clear junction line; subsequently, zygote nucleus formed and karyotheca became faint; at 15 min pest-insem- ination, first karvokinetic division was develoued.
基金Supported by the Ministry of Science and Technology of China(No.2011BAD13B09)the Project of a Special Fund for Public Welfare Industrial(Agriculture)Research of China(No.200903001-5)
文摘Aquaculture production efficiency may increase by using feed additives. This study investigated the effects of different dietary additives [w/w: 2% small peptides, 0.01% probiotics( Bacillus licheniformis) and 0.2% prebiotics(inulin)] on growth performance, digestive enzyme activities, and oxidative stress in juvenile Epinephelus coioides reared in artificial seawater of two salt concentrations(13.5 vs. 28.5). Weight gain rate was significantly higher in fish fed the diet supplemented with small peptides, B. licheniformis, inulin, or synbiotics than that in fish fed the basal diet; the greatest weight gain rate was found in fish fed the small peptide treatment [56.0% higher than basal diet]. Higher feed efficiency was detected in fish fed the diet supplemented with small peptides than that of fish in the other dietary treatments. Total protease activity in the stomach and intestines was highest in fish fed the small peptide-treated diet, whereas lipase activity was highest in those fed synbiotics(combination of Bacillus licheniformis and inulin) than that in fish fed the other treatments. Antioxidant enzyme(total superoxide dismutase and catalase) activities and hepatic malondialdehyde content were higher in fish receiving the dietary supplements and maintained in artificial seawater containing 13.5 salinity compared with those in the control(28.5). Hepatic catalase activity in grouper fed the diets with small peptides or synbiotics decreased significantly compared with that in control fish. Overall, the three types of additives improved growth rate of juvenile grouper and digestive enzymes activities to varying degrees but did not effectively improve antioxidant capacity under low-salinity stress conditions.
基金This study was supported by the National Natural Science Foundation of China under contract Nos 40306023 and 40576064the Important Program of Science and Technology of Fujian Province in China under contract No.2004NZ03.
文摘Using multi-molecular marker technologies and based on morphological criteria, the genetic relationship between Epinepheelus malabaricus and E, coioides was examined in the hope of resolving the long-standing issue of identifying these two species. Results showed that： （ 1 ） E. coioides and E. malabaricus should be identified as two species, the consistency of mitochondrial DNA cytochrome b gene sequence between E. malabaricus and E. coioides is 94.4%, and the genetic similarity by AFLP was 0.753 9 ; （2） Hybridization exists between E. malabaricus and E. coioides, the specific RAPD and AFLP fragments are found to be useful in the identification of these two species, and the genetic properties （both with exterior and inheritance） of hybrid is significantly biased to the male parents ; and （3） AFLP was a potentially powerful tool in constructing the genetic linkage map for these two groupers.
基金Supported by NNSF of China (No. 39625006, 39970584)the Knowledge Innovation Program of CAS, China (No. ZKCX2–211)
文摘Effects of water temperature （17, 21, 25, 30 and 35℃） and body size （14.75-281.41 g initial body weight） on food consumption, growth, feed conversion, and dry matter content in orange-spotted grouper fed to satiation were investigated. The combined effect of temperature （T, ℃） and body weight （W, g） on maximum food consumption （Cmax, g/day） was described as： InCmax=-7.411＋0.828 InW＋0.317T4）.004 7T2, and the optimum feeding temperature was 33.9℃. The combined effect of temperature and body weight on growth （G） was described as： lnG=-4.461-0.2081nW＋0.394T-0.006 3T^2. The optimum growth temperature was 31.4℃, whereas overall growth rates were high at 25, 30 and 35 ℃. Feed conversion efficiencies （FCE, %）, increasing first and then decreasing with increasing temperature, averaged from 1.8 to 2.1 in terms of dry weight of food fish. The optimum temperature for FCE tended to be lower than that for growth or feeding. Dry matter content increased with both increasing water temperature （17, 25, 30 and 35℃） and body weight, and the combined effect of temperature and body weight on dry matter content （DM, %） was described as： lnDM =3.232＋0.01 4 lnW-0.004 4T＋0.001 2TInW.
文摘Serum biochemical parameters are important aspects in the management of endangered species. The values of these parameters can be used for confirming the maturity and for monitoring any changes in the quality of waters and related soils. The aim of this research was to determine the reference values of biochemical factors in Acantopagrus latus and Epinephelus coioides. Blood samples were collected from captured fish from coastal waters of Chabahar (Ramin waterfront). Serum levels of glucose, Blood Urea Nitrogen (BUN), cholesterol (CHO), triglyceride, total protein, albumin, calcium (Ca2+), phosphorus (P), sodium (Na+), bilirubin and potassium (K+) were measured. The results showed that the levels of albumin and bilirubin in E. coioides were significantly higher than A. latus and there were significant differences in all of the serum values (except P and glucose) between A. latus and E. coioides (P < 0.05). It can be concluded that the values of blood biochemical parameters may be affected by physiological factors such as the species of fish.
基金This work was supported by the National Marine 863 Projects of China (Nos. 2003AA621010 2003AA621110) the NationalNatural Science Foundation of China (No. 39970586) Key Project of Scientific and Technological Research of the Ministry ofEducation (No
文摘研究斜带石斑鱼生长激素分泌及其 mRNA 表达的调控规律对于性别分化的控制、临床药物的选择,以及石斑鱼的增养殖等均具有重要的理论意义和实践意义。本文应用静态孵育系统, 采用放射免疫测定法和化学发光液相杂交实验, 研究GnRH 和 DA 对斜带石斑鱼 GH 分泌、GH mRNA 合成的调控作用。100 nmol/L sGnRH 作用斜带石斑鱼脑垂体碎片 1~24 h,明显促进GH的释放和GH mRNA的合成, 并具有时间依存性; 10 nmol/L^1 μmol/L sGnRH作用1 h 能明显促进斜带石斑鱼脑垂体释放GH,促进GH mRNA的合成, 表现出明显的剂量效应。100 nmol/L、1 μmol/L mGnRH 作用1 h 以一定的剂量依存方式促进 GH 的释放、促进 GH mRNA的合成,但 mGnRH 的效应比相应剂量的 sGnRH 的作用弱。APO 为 DA 受体的非选择性激动剂,不同剂量APO 对斜带石斑鱼脑垂体碎片的作用结果显示, 10 nmol/L^1 μmol/L APO 以剂量依存方式促进斜带石斑鱼脑垂体碎片释放GH、促进 GH mRNA的合成;1 μmol/L APO 作用 12 h 以上明显促进GH 的释放和 GH mRNA的合成,并随时间的延长而增加。与 sGnRH 对斜带石斑鱼 GH 释放、GH mRNA合成的作用相比, APO 的作用较弱。本文研究结果证实GnRH 和 DA能促进斜带石斑鱼脑垂体GH 释放和GH mRNA合成。
